Hot-air furnace



3 Sheets-Sheet} 1.

{No Model.)

R. J. SGHWAB.

HOT AIR FURNACE.

No. 546,714. Patented Sept. 24, 1895.

m'fizesses:

No Model.) 3 Sheets-Sheet 2.

t R. J. SOHWAB.

HOT AIR FURNACE.

No. 546,714. Patented Sept. 24, 1895.

ANDREW EGRAIIAM, PHUTOLITHQWASHINGTDN. DE,

(No Model.)

v3 Sheets-Sheet 3. B. J. SCHWAB.

HOT AIR FURNAGE.

No. 546,714. Patented Sept. 24, 1895.

w n 6 m AN DREW BJSRAHAM. PHUTD'U'I'HQWASHINGIONDL UNrrsn Srn'rns PATENT Gaston.

RUDOLPH J. SCHWAB, OF MILWAUKEE, WISCONSIN.

HOT-AIR FURNACE.

SPECIFICATION forming part of Letters Patent No. 546,714., dated September 24, 1895.

Application filed August 23, 1 890- To all whom it may concern.-

Be it known that I, RUDOLPH J. SOHWAB, of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and usefulImprovements in Hot-Air Furnaces; and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the artto which it pertains to make and use the same, reference being had to the accompanying drawings, and to theletters of reference marked thereon, which form a part of this specification.

The main objects of my invention are to prevent the escape of gas, to facilitate the running and cleaning of the furnace, to increase its efficiency, and to improve its construction in certain particulars; and it consists, essentially, of certain peculiarities of construction and arrangement hereinafter particularly described, and pointed out in the claims.

In the accompanying drawings like letters designate the same parts in the several figures.

Figure l is a perspective view of a furnace to which my improvements are applied, portions of the casing, drum, and dome being broken away to disclose the arrangement of interior parts. Fig. 2 is a vertical section of a portion of the dome, its surrounding drum and deflector, the strips forming packingrooves at the top of the drum being omitted. Fig. 3 is a horizontal section of the same on the line w 00, Fig. 2. Fig. 4E is a sectional view of one of the clean-out doors in the bottom of the drum. Fig. 5 is a sectional view of the water pan and the associated parts. Fig. 6 is a ver-, tical cross-section of one side of the drum, showing the division-plate and self-packing or cup joints. Fig. 7 is asection at right angles to that shown in Fig. 6 of the division-plate and a portion of the drum, and Fig. 8 is a horizontal section of the same.

A represents the body of the furnace, B the ash-pit, O the dome, and E a double sheetmetal casing of the usual or any suitable form and construction.

D is an annular drum, the sides of which are preferably formed of sheet metal attached at the top and bottom to cast-iron rings (1 d, which are curved in cross-section, as shown in Figs. 1, 2, and 6, to give them greater stiffness smut. 362,826. (No model.)

and prevent their warping and cracking by expansion and contraction, and are formed around the edges with flanges for the attach- 55 ment of the sheet-metal sides. This drum is supported upon and attached to arms 0 0, cast with and projecting outwardly from the ring 0', which constitutes the base of the dome and rests upon the top of the body A. By thus supporting and permanently fastening the drum D to the dome the furnace can be set up and shipped more conveniently.

c is a pipe or flue leading out of one side of the dome into the drum D. At one side of the flue c the drum is divided transversely by a division-plate orpartition 1 on the opposite side of which the smoke-flue c connects with the outer side of said drum. The smoke and products of combustion entering the drum through the flue c are compelled by the partition (i to pass entirely around the furnace through said drum D before they can escape through the smoke-flue c on the opposite side of said partition, and thus the heat, which would otherwise escape into the chimney and be lost, is utilized in heating said druin, which presents a large surface to the air passing upwardly around it.

The partition-plate d is formed on theside edges with flanges 61 (1 which present wide bearingsurfaces to the Walls of the drum D. It -is'also formed at the top with a packinggroove, in which is inserted a tongue 01 on the upper ring d, and it is seated at the bottom in a packing-groove formed by two flanges or tongues d d on the lower ring d. Bythis .construction of the plate d tight joints are produced, and leakage of gas around its edges and its direct passage from the flue c to the flue are prevented.

Gas-tight joints between the sides of drum D and the upper ring 01 are produced by riveting strips d d to the upper edges of the side plates, as shown in Figs. 6 and 7, so as to form packingrooves, in which the flanges on the ring (I are inserted- These grooves are filled with asbestos or other suitable packing which will withstand heat and produce gastight 'oints.

J For the purpose of removing the soot which collects in the bottom of the drum D, I form openings in the lower ring d, which are closed by removable doors at, provided with fastenings (Z (P, consisting of buttons pivoted therein and arranged to be turned outwardly, so as to engage the edges of the openings, as shown in Fig. 4.

Between the dome O and drum D, I interpose cylindrical plates F F, which are heated by radiation from the adjacent surfaces of said dome and drum and impart their heat to the upwardly-passin g air-currents. These plates, preferably two in number, are held in place by suitable fastenings and are attached to each other by bolts ff, upon which thimbles are placed to hold said plates at the proper distance apart.

To prevent the smoke and products of combustion from passing directly from the firepot into the flue c',I provide a shield-shaped deflector G, which is suspended by means of an arm 9 at its upper edge upon a hook or hooks g in the top of the dome, and is fitted to and rests upon its edges snugly against the inside of said dome on each side of and below said flue. The smoke and heated currents are thereby compelled to pass upwardly into the top of the dome over the upper edge of said deflector before they can escape through the flue 0 into the drum D, and the walls of said dome are thus more evenly heated. I provide the deflector G at the lower edge with a loop or ring into which a hook passed through the door of the furnace may be inserted, and by this means the shield is drawn away at its lower edge from the drum, thereby allowing the soot, dust, and ashes collected therein to drop into the fire-pot. When released the shield swings by its own weight into place again.

To break and spread the air-currents enteriug the space around the base of the furnace, I interpose between the fire-pot A and easing E a horizontal screen or perforated plate II, to the under side of which is attached a vertical cylindrical plate 72., which separates the incoming air, directing a portion of it over the surface of the fire-pot and a part through the outer portion of the perforated plate 11. It is heated by radiation from the adjacent walls of the body of the furnace and imparts its heat to the air coming in contact with it.

K represents a water-pan, the front side of which is inclined outwardly toward the top, so as to project from the casing E when inserted therein. The opening through the easing for the reception of the pan K is provided with a frame I, and the pan is formed with a flange 7;, which overlaps this frame and closes the joints between it and said pan when the latter is in place, as shown in Figs. 1 and 5. The pan K is supported when in place upon brackets L, attached to the inside of the easing E and bolted through the same to projections it i on the under side of the frame I, as seen in Fig. 5. The frame 1 stiffens the easing around the water-pan opening and assists to hold the brackets L and water-pan firmly in place. That portion of the pan K opening outside of the casing E is provided with a hinged or pivoted lid 70, which maybe turned aside for the purpose of refilling the pan without withdrawing the latter from the casing. This construction and arrangement of the water-pan permits of filling the same with an ordinary pail or bucket directly, and is much more convenient than pans which are entirely within the furnace-casing and must be removed therefrom for filling or be refilled by means of a pail or vessel having a spout which may be inserted through the opening in the casing. My construction also admits of readily removing the pan from the furnace and affords access to the adjacent clean-out door d for the purpose of cleaning the drum D, when desired.

The details of construction and arrangement of the several improvements hercinbefore described may be variously modified without departure from the spirit of my invention.

I elaim 1. The combination in a furnace with the dome provided with a flue opening through the side thereof, of a deflector suspended within said dome from said flue and movable at its lower edge away from the walls of the same, substantially as and for the purposes set forth.

2. The combination in a furnace with the dome provided at the base with outwardly projecting arms, of an annular drum encircling said dome and supported upon said arms, substantially as and for the purposes set forth.

3. In a furnace, an annular heating drum constructed of sheet iron or steel sides and cast iron top and bottom rings curved outwardly in cross section and having tapering marginal flanges, the sheet metal sides overlapping both flanges on each ring on their outer sides, substantially as and for the purposes set forth.

4:. In a furnace, an annular heating drum having its bottom concave in cross section on the upper inner side and formed in the lower portion thereof with clean out openings and removable doors arranged to close said openings, substantially as and for the purposes set forth.

5. The combination in a furnace with the fire pot and easing, of a perforated diaphragm interposed horizontally between said fire pot and casing, and a vertical plate attached to the under side of said diaphragm between its inner and outer edges and surrounding the fire pot, substantially as and for the purposes set forth.

6. In a furnace, the combination with an annular drum having induction and eduction openings near together but out of line, of a partition plate between said openings providcd with extended side edges presenting wide bearing surfaces to the walls of said drum, substantially as and for the purposes set forth.-

7. In a furnace, the combination with an annular drum having induction and eductionopenings out of line with each other, of a partition plate having a packing groove at the top in which is inserted a tongue on the top of the drum and seated at the bottom in a packing groove in the bottom of the drum substantially as and for the purposes set forth.

8. In a furnace, the combination with an annular drum having induction and eduction openings out of line with each other, of a partition plate located between said openings RUDOLPH J. SCHWVAB.

Witnesses:

CHAS. L. Goss, E. O. AsMUs. 

